Non-Reflecting boundary for air domain to simulate infinite air: Blast waves
Non-Reflecting boundary for air domain to simulate infinite air: Blast waves
(OP)
Hello All,
We are performing contact explosion analysis of RC members using LS-Dyna. A simple model would consist of two parts: a member subjected to blast and an air domain. The member is modeled as Lagrangian element and the air and explosive are modeled as ALE elements. A common problem faced my most of us is to decide the extent of air domain that will capture adequate response of the member under consideration. Especially in case of contact explosion the air domain has to be quite large in order to capture the global response as well. The reason to keep a large air domain is that the blast waves get reflected from the boundary of air domain and exert additional load on the member. There is a keyword *BOUNDARY_NON_REFLECTING available however it seems to work only with Lagrangian elements. The blast waves (ALE fluid) are still reflected at the boundary with this keyword.
I would like to know if there is a way to provide any boundary condition to the air domain so that the blast waves generated due to the the detonation of explosive is not reflected at the boundary. A finite air domain can then be used to simulate an infinite air domain thereby making the model considerably small.
Looking forward to some smart solutions.
Best,
Alok
We are performing contact explosion analysis of RC members using LS-Dyna. A simple model would consist of two parts: a member subjected to blast and an air domain. The member is modeled as Lagrangian element and the air and explosive are modeled as ALE elements. A common problem faced my most of us is to decide the extent of air domain that will capture adequate response of the member under consideration. Especially in case of contact explosion the air domain has to be quite large in order to capture the global response as well. The reason to keep a large air domain is that the blast waves get reflected from the boundary of air domain and exert additional load on the member. There is a keyword *BOUNDARY_NON_REFLECTING available however it seems to work only with Lagrangian elements. The blast waves (ALE fluid) are still reflected at the boundary with this keyword.
I would like to know if there is a way to provide any boundary condition to the air domain so that the blast waves generated due to the the detonation of explosive is not reflected at the boundary. A finite air domain can then be used to simulate an infinite air domain thereby making the model considerably small.
Looking forward to some smart solutions.
Best,
Alok





RE: Non-Reflecting boundary for air domain to simulate infinite air: Blast waves
I have the same problem, do you know how to solve this? I tried alternatives but none worked.
Thank you